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.Dd April 22, 2021
.Dt BUS_CHILD_PNPINFO 9
.Os
.Sh NAME
.Nm BUS_CHILD_PNPINFO
.Nd "obtain the plug and play information from a device"
.Sh SYNOPSIS
.In sys/param.h
.In sys/bus.h
.In sys/sbuf.h
.Ft void
.Fn BUS_CHILD_PNPINFO "device_t dev" "device_t child" "struct sbuf *sb"
.Sh DESCRIPTION
The
.Fn BUS_CHILD_LOCATION
method returns the identifying information about the
.Dv child
device.
This information is called the plug and play (pnp) details by some buses.
This information is a series of key=value pairs.
The string must be formatted as a space-separated list of key=value pairs.
Names may only contain alphanumeric characters, underscores ('_') and hyphens ('-').
Values can contain any non-whitespace characters.
Values containing whitespace can be quoted with double quotes ('"').
Double quotes and backslashes in quoted values can be escaped with backslashes ('\').
.Pp
The pnpinfo is defined as a series of characteristics of the
.Dv child
device that are independent of which drivers are attached, but
are used to allow drivers to claim a device.
Typically, plug and play information encodes who made the device, what the model
number is, and some generic details about the device.
By convention, only the generic information about the device that's used by
drivers on that bus to decide on accepting the device is reported.
Other configuration information (such as the cache burst size) needed for the
operation of the device, but that doesn't distinguish it broadly from other
devices is not reported.
.Sh SEE ALSO
.Xr bus 9 ,
.Xr device 9
